Bags of Web in My Trees Again?

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Fall Webworms are making their presence know around our area. Even though you may have seen webs in your trees this past spring, these web makers are different visitors. They are making their homes at the tips of the branches, rather than down between the branch crotches, like the earlier season Easter Tent Caterpillars. Their appearance is completely different as well.

These tiny, hairy caterpillars hatch and grow into pale to dark caterpillars about 1.5 inches long and are covered with long hairs. Although we see them most often on sourwood, persimmon and pecan trees, Fall Webworms actually feed on over 600 species of trees and shrubs causing mostly cosmetic damage to shade trees because of the ugly webs they make around the leaves they’re eating. While they’re not appealing to look at, the danger to the tree that they’ve chosen to feed on isn’t horrible. Since it is already mid summer the trees have been storing food for a while now, and fall is on the way so the the tree would lose the leaves anyway.

Fall Webworms mature in about 6 weeks, leave the web and pupate on or in the soil. They’ll spend the winter in cocoons hidden in mulch, leaf debris and in the soil, so clearing and cleaning up at the end of the season can help reduce the population of this pest before the moth stage can emerge.

If you feel that you must take action to deal with the caterpillars, they can be easily destroyed or dislocated by pulling down the webs and destroying them if the webs are within reach of a stick or pole. This also exposes caterpillars to bird and wasp predation. Please remember, just as with the Eastern Tent Caterpillar webs, trying to burn them out of the tree

is much more dangerous than it is effective and is not recommended. If the webs are not within reach a power sprayer may be able to reach higher in the tree.  Because the web bags will enlarge as the caterpillars grow and need to feed, remember to cover the foliage closest to the web mass with the pesticide product you choose. Spraying the web itself does not give good contact with the caterpillars. Use pesticides only according to the directions on the label. Read more about control measures at https://www.ces.ncsu.edu/depts/ent/notes/O&T/trees/note46/note46.html

Minda Daughtry is Horticulture Agent for North Carolina Cooperative Extension in Lee County.

Written By

Photo of Minda DaughtryMinda DaughtryExtension Agent, Agriculture - Horticulture (919) 775-5624 minda_daughtry@ncsu.eduLee County, North Carolina
Posted on Aug 25, 2017
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